Cod sursa(job #945448)
Utilizator | Data | 1 mai 2013 22:11:11 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 90 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
#include <fstream>
using namespace std;
int nrp,n,i,j;
bool a[2000010];
ifstream f("ciur.in");
ofstream g("ciur.out");
int main()
{ f>>n;
nrp=1;
for (i=3;i<=n;i+=2)
for (j=3*i;j<=n;j+=i)
a[j]=1;
for (i=3;i<=n;i+=2)
if (a[i]==0) nrp++;
g<<nrp;
return 0;
}